In a conventional pneumatic tire, in order to improve performance on snow, there has been adopted a tread pattern comprising circumferential direction wide-width grooves that are provided at both sides with a tire equatorial plane interposed therebetween and that form a circumferential direction rib, circumferential direction narrow-width grooves that are provided at tire width direction outer sides of the circumferential direction wide-width grooves, transverse grooves that traverse the circumferential direction wide-width grooves and the circumferential direction narrow-width grooves, and sub-grooves that substantially divide into halves rhomboid land portions delineated by the circumferential direction wide-width grooves, the circumferential direction narrow-width grooves and the transverse grooves (for example, refer to Patent Document 1). In the pneumatic tire of Patent Document 1, due to the combination of the circumferential direction wide-width grooves and the circumferential direction narrow-width grooves, straight traveling stability and cornering performance are improved, by setting an angle of inclination of the transverse grooves with respect to the tire circumferential direction, traction performance on snow is improved, and due to the sub-grooves that substantially divide into halves the rhomboid land portions, cornering performance on snow is improved.    Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 2000-255217